Objective To explore the trajectories of adherence to a sodium-restricted diet and the influencing factors in patients with heart failure during the vulnerable period, and to provide a reference for developing targeted interventions. Methods A convenience sampling method was used to recruit 252 patients with heart failure, then they were investigated by using a general information questionnaire, the Dietary Sodium Restriction Questionnaire, the Social Support Rating Scale, the Self-rating Anxiety Scale, and the Self-rating Depression Scale on the day of admission, and their adherence to a sodium-restricted diet was reassessed at 2 months and 3 months after discharge. Latent class growth modeling was employed to identify distinct trajectory classes, and univariate analysis and multivariate logistic regression were used to analyze the influencing factors. Results Three distinct trajectories of adhe-rence to a sodium-restricted diet were identified: a high-level adherence group (41.3%), a medium-level group with an initial decline followed by an increase (32.1%), and a low-level adherence group (26.6%).Age, educational background, salty taste pre-ference, average monthly household income per capita, and social support were the influencing factors for the latent classes of adherence behavior （all P＜0.05）. Conclusion The trajectories of adherence to a sodium-restricted diet during the vulnerable period are heterogeneous among patients with heart failure. Healthcare providers can develop targeted interventions based on the influencing factors associated with each trajectory class to improve patients′ adherence levels.